.box {
    margin: auto;
    position:absolute;
    top:20%;
    left:35%;
    width: 500px;
    height: 350px;
    border: 1px #111 solid;
    display: none; /* 默认对话框隐藏 */
}
.box{
    background-color:white;
}
.box.show {
    display: block;
}

.box .x {
    font-size: 18px;
    text-align: right;
    display: block;
}

.box input {
    width: 80%;
    font-size: 18px;
    margin-top: 18px;
}
span{
    color:black;
    font-weight:bold;
}
table {
    text-align: center;
}

#t {
    text-align: center;
}